The present invention relates to a data processing apparatus for processing text data, graphics data and the like, and more particularly to a method of changing a screen image on a display unit and data processing apparatus using such a method, suitable for efficient use in sequentially displaying a number of screen image data one after another in the manner matching a human behavior.
In a conventional data processing apparatus, in order to turn a page on a display screen, a predetermined key of a keyboard is depressed or a mouse is clicked when the mouse cursor is moved to a predetermined area on the screen.
Data processing apparatus of this type are disclosed in, e.g., Japanese Patent Laid-open Publications JP-A-62-140124 62-214423, 62-229317, 62-212717.
Personal computers, word processors and the like prevail in the general public. It is therefore desired to allow more efficient use of computers whose operation matches human behavior. One of operations used with computers is an operation to instruct a display change of a screen image. Sequentially displaying a number of screen image data on a screen one after another corresponds to manually turning pages of a voluminous book. A conventional screen image changing operation (screen image selection operation) using a keyboard or mouse buttons is far from the manual page turning operation. Further, there is a case where only a part of a large graphics image is displayed on the screen of a CAD apparatus or the like. If a keyboard or a mouse button is used in changing the image on the screen, it is difficult for an operator to recognize the continuity of the screen image when it is changed from one part to another. Also in this case, the operation does not match human behavior.